angelfish pregnant?

Question
I have 3 angelfish. 2 Gold and 1 halfblack. The 2 gold seemed to have 'paired off' and I've noticed that the belly of one is becoming swollen. They are both eating very well and seem very happy and healthy. Could they be ready to spawn and is there anything I can do to expedite the process?  I have not tested the water and have no idea of it's quality. It's a new 90 gallon tank with a rena canister filter (using only carbonated charcoal as filter media)and the water comes from an artesian well. I think the pH (from our well)is mostly neutral. It is also slightly hard (evidenced by scale on my kettle.
They are the first fish in the tank and I think this may be prompting the possibility of them spawning since it's still very clean.  I change the water once every 3 weeks and sometimes even longer.

Answer
Hi Bonnie,
 They very well might be thinking about laying eggs.

 Don't mess with the pH but you should consider doing more frequent water changes.  It is much better to change 20% of the water each and every week than it is to change more of the water less often.   

-- Ron
  rcoleman@cichlidresearch.com
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